Electrode.



' UNITED STATES PATENT ornron;

CARL B. KRUEGER, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, CORPORATION OF NEW YORK.

Patented May 13, 1913.

ELECTRODE.

1,061,758, Specification of Letters Patent.

No Drawing.

which the following is a specification.

My invention has reference to an electrode a of the flaming or luminous type, and par- .cipal light giving constituents.

ticularly to such an electrode in which titan iferous material 'and especially metallic titanium or titanium carbid or a mixture of the same is present as one of the prin- Materials of the above character are among the most eflicient light producing vmaterials known, but an electrode containing such materials forms a layer of non-conducting slag upon its arcing surface, which causes, the arc to jump around irregularly. My theory of, the reason for this is thatthe thickness of the layer is uneven and the arc shifts from one point to another, seeking the path of least resistance. Whatever may be the correct theory, however, I find that such a non-conducting-layer is-formed in an electrode in which metallic titanium or titanium carbid or a mixture of the two is present in substantial quantities and that such a layer seriously interferes with the burning of the arc. The titanium arc is long and thin and naturally unsteady and when this unsteadiness is Increased by the layer of slag, the arc collapses frequently, causing correspondingly frequent and objectionable feeding operations. Moreover, such a non-conducting layer of slag on thearcing face of the electrode often prevents the are from being properly struck when the electrodes are separated for this purpose and frequently the electrodes are separated and agaln brought together in rapid successlon, producin a disagreeable pounding of the electro es.

I have found that the formation of such a non-conducting layer in an electrode in which titaniferous material is present can be preventedyby the addition thereto of a small percentage of cupreous material and the, feeding operation of the lamp is thereby greatly improved. -Such an electrode burns with a black conducting tip and is entirely free from the non-conducting layer and the evils accompanying the same. I have used several cupreous materials such as metallic Application filed pctobcr 16, 1911. Serial No. 654,878.

copper, co per oxid, copper chlorid and copper fiuori andthese all Well serve the purposes of my invention. It will be seen, therefore, that my invention covers broadly ,any cupreous material,-the beneficial effects apparently being due to the presence of the copper. I have obtained excellent results by taking titanium carbid, which I procured in the market and which contained a small percentage, say six or seven per cent, of carbon, and mixing therewith two per cent. of finely divided metallic copper. I have also obtained excellent results 'by' taking titanium carbid which was made in the resistance furnace and which contained a comparatively large percentage of carbon, for example, twenty-five or thirty per cent, and mixing therewith the same amount of me tallic copper. Now the theoretical amount ofcarbon present in pure titanium carbid is approximately twenty per cent, so that in the first case the mixture was composed of titanium carbid and a large ercentage of metallic titanium, while in t e second case titanium carbid was mixed with a substantial percentage of carbon. It will .be

seen therefore that my invention is useful in, electrodes in which the amount of titanium carbid varies widely and that it is equally applicable to an electrode composed of pure titanium carbid and to an electrode within my invention. Furthermore, when copper compounds, instead of the metal copper, are used, I have found that it is desirable to use a somewhat larger percentage, usually about three per cent. I have found that if more than a small percentage of copper or a copper compound is present, the arc becomes non-luminous. If but a small percentage of on reous material is used, however, the luminosity of the arc is not interfered with. These titanium carbid electrodes are usually made by filling the carbid mixture into an iron tube and compacting it within the same.

My invention is also applicable to what is known in the art as a flaming electrode, that is, an electrode in which free carbon ent to produce a slag. When free carbon,-

v or metallic titanium or a mixture of the two is added to the electrode in substantial quan fl tities but in which enough titanium or ti tanium carbid or a mixture of these is pres however, is present in substantial quantities, there is usually not-the same necessity for the addition. of cupreous materials, as the presence of the carbon itself when used in substantial quantities .has a tendency to steady the arc.

I have found thatthe cupreous material can advantageously be introduced into the electrode by. adding it to the titanium carbid and subsequently forming theelectrode, or the cupreous material may be 'miXed with the rutile. and carbon from which the titanium carbid isformed. What I claim as new and desire to secure by Letters Patent ofthe United States, is,-

1. An arc light electrode containing titaniferous material and a small percentage of a cupreous material.

2. An arc light electrode composed of titaniferous material which produces a slag in -burning and a small percentage of a cupreous material. .3. An ,are light electrode containing titanium" arbidand a small percentage of cupreous" material.

4. An arc light electrode containing titaniferous material and an admixture of a small percentage of metallic copper.

5. An are light electrode containing titanium carbid and a small percentage of metallic copper. v

6. An arc light electrode composed mainly of titaniferous materialv and an admixture of between one and three 'per cent. of a'cupreous material.

7. An are light electrode composed mainly of titaniferous material and an admixture of between one and three per cent. of finely dividedmetallic copper.

Tn witness whereof, I have hereunto set my hand this 13th day of Qctober, 1911.

ARL R. KRUEGER.

lVitnesses:

BENJAMIN B. HULL HELEN ORFORD. 

